81896859 has 64 divisors (see below), whose sum is σ = 145612800. Its totient is φ = 44906400.

The previous prime is 81896827. The next prime is 81896869. The reversal of 81896859 is 95869818.

It is not a de Polignac number, because 81896859 - 2⁵ = 81896827 is a prime.

It is a super-3 number, since 3×81896859³ (a number of 25 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (81896869) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 129474 + ... + 130104.

It is an arithmetic number, because the mean of its divisors is an integer number (2275200).

Almost surely, 2^81896859 is an apocalyptic number.

81896859 is a deficient number, since it is larger than the sum of its proper divisors (63715941).

81896859 is a wasteful number, since it uses less digits than its factorization.

81896859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 693 (or 687 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 54.

The square root of 81896859 is about 9049.6883371749. The cubic root of 81896859 is about 434.2659200525.

The spelling of 81896859 in words is "eighty-one million, eight hundred ninety-six thousand, eight hundred fifty-nine".